Abstract

Elite controllers or suppressors (ES) are HIV-1 infected patients who maintain viral
loads of < 50 copies/ml without antiretroviral therapy. CD8+ T cells are thought to
play a key role in the control of viral replication and exert selective pressure on
gag and nef in HLA-B*57 positive ES. We previously showed evolution in the gag gene of ES which surprisingly was mostly due to synonymous mutations rather than non-synonymous
mutation in targeted CTL epitopes. This finding could be the result of structural
constraints on Gag, and we therefore examined the less conserved nef gene. We found slow evolution of nef in plasma virus in some ES. This evolution is mostly due to synonymous mutations and
occurs at a rate similar to that seen in the gag gene in the same patients. The results provide further evidence of ongoing viral replication
in ES and suggest that the nef and gag genes in these patients respond similarly to selective pressure from the host.